Treatment satisfaction and dissatisfaction in patients with chronic low back pain

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.This thesis explores treatment satisfaction and dissatisfaction in patients with chronic low back pain (CLBP). Chapters 1 and 2 provide background on CLBP, and treatment satisfaction and dissatisfaction. Chapter 3 presents study 1, the systematic review which identified research concerning treatment satisfaction and dissatisfaction in patients with CLBP. Findings indicated a need to define the concept, and establish appropriate measurement based on patient input and evidence to support the reliability and validity of items. Chapter 4 presents study 2, a qualitative study. Ten patients with CLBP taking medication and/or receiving physiotherapy were interviewed. A conceptual model of CLBP and a thematic map of treatment satisfaction and dissatisfaction were developed. Satisfaction was related to being 'happy' or 'pleased', and maintaining normal functioning. Treatment not working, causing discomfort, or negatively affecting health-related quality of life, as well as inconvenience of medication, lack of information, not feeling involved in treatment decisions, lack of trust and confidence in healthcare professionals, and being misdiagnosed or undiagnosed, were associated with dissatisfaction. Chapter 5 documents the development of the CLBP Treatment Satisfaction Questionnaire, based on patient input from study 2. Cognitive debriefing showed items were relevant and understood by patients. Chapter 6, study 3, explored the psychometric properties of the questionnaire. The longitudinal design involved data collection from 249 patients, some of whom participated in follow-ups. Results indicated that treatment satisfaction/dissatisfaction involves an appraisal of the following seven domains: 'Information Provided about Back Pain and Treatment', 'Burden of Back Pain', 'Impact of Back Pain and Treatment on Relationships', 'Satisfaction with the Treatment Process', 'Problems with Side Effects of Medication', 'Adherence to Physiotherapy', and 'Medication Acceptability'. Some evidence of reliability and validity are presented. This thesis concludes with Chapter 7, a discussion of the main findings of the studies, strengths and limitations, and recommendations for future research.Funded by Mapi Value

Opposing effects of recirculated gases during cranking on cold start of diesel engines

ABSTRACT OPPOSING EFFECTS OF RECIRCULATED GASES DURING CRANKING ON COLD START OF DIESEL ENGINES by RAFIK ROFAIL August 2011 Advisor: Dr. Naeim Henein Major: Mechanical Engineering Degree: Doctor of Philosophy Enhancing cold start of DI diesel engines is the motivation behind this study. A new control strategy is proposed to reduce the cranking period and the white smoke emissions. In the strategy, the gases leaving the cylinder during the cranking period are recycled back into the intake manifold using two different methods. In the first method the engine-out gases during cranking are recirculated into the intake manifold and their rate is controlled by a CGR (Cranking Gases Recirculation) valve, without applying any back pressure on the engine. In the second method a butterfly valve is installed in the exhaust system after the turbocharger to increase the back pressure and the rate of recirculated gases. Since there is no combustion during cranking, these gases contain evaporated hydrocarbons (HCs) and partial oxidation products such as formaldehyde (HCHO). HCs and HCHO have two opposing effects. HCs enhance the autoignition process, while the HCHO has an opposite effect. These opposing effects are being investigated by three different approaches. The first is experimentally in a multi-cylinder proto-type engine. The second is using high speed imaging in an optically accessible engine. The third is by using CFD and chemical kinetic simulation to gain a better understanding of the effect of the recirculated gases on the autoignition process during cold starting of a direct injection diesel engine. Cold start experiments are conducted on a 1.2L Ford DIATA 4-cylinder, 16-valve, 70 mm bore, 78 mm stroke and 19.5 compression ratio, water cooled, turbocharged and intercooled diesel engine. The engine is equipped with a common rail injection system, EGR system and a swirl control mechanism. The engine is installed in a cold room and the ambient temperature is electronically controlled. Before starting, the engine is soaked at the desired room temperature for at least eight hours. The analysis of the data demonstrated the effect of two CGR methods on reducing the cranking period and HCs emissions. The images showed the effect of aldehydes on hindering the autoignition and combustion processes. The simulation covered a wide range of the hydrocarbons and aldehydes concentrations and their effect on the ignition delay. The simulation results agreed with the experimental findings. The results of this work will help in developing strategies to reduce the cranking period, fuel consumption and white smoke emitted during cold starting of diesel engines. In addition, a more understanding will be developed of the role of aldehydes in combustion instability and misfiring after first firing experienced in cold starting of diesel engines

Using qualitative methods to inform the trade-off between content validity and consistency in utility assessment: the example of type 2 diabetes and Alzheimer's Disease

<p>Abstract</p> <p>Background</p> <p>Key stakeholders regard generic utility instruments as suitable tools to inform health technology assessment decision-making regarding allocation of resources across competing interventions. These instruments require a 'descriptor', a 'valuation' and a 'perspective' of the economic evaluation. There are various approaches that can be taken for each of these, offering a potential lack of consistency between instruments (a basic requirement for comparisons across diseases). The 'reference method' has been proposed as a way to address the limitations of the Quality-Adjusted Life Year (QALY). However, the degree to which generic measures can assess patients' specific experiences with their disease would remain unresolved. This has been neglected in the discussions on methods development and its impact on the QALY values obtained and resulting cost per QALY estimate underestimated. This study explored the content of utility instruments relevant to type 2 diabetes and Alzheimer's disease (AD) as examples, and the role of qualitative research in informing the trade-off between content coverage and consistency.</p> <p>Method</p> <p>A literature review was performed to identify qualitative and quantitative studies regarding patients' experiences with type 2 diabetes or AD, and associated treatments. Conceptual models for each indication were developed. Generic- and disease-specific instruments were mapped to the conceptual models.</p> <p>Results</p> <p>Findings showed that published descriptions of relevant concepts important to patients with type 2 diabetes or AD are available for consideration in deciding on the most comprehensive approach to utility assessment. While the 15-dimensional health related quality of life measure (15D) seemed the most comprehensive measure for both diseases, the Health Utilities Index 3 (HUI 3) seemed to have the least coverage for type 2 diabetes and the EuroQol-5 Dimensions (EQ-5D) for AD. Furthermore, some of the utility instruments contained items that could not be mapped onto either of the proposed conceptual models.</p> <p>Conclusions</p> <p>Content of the utility measure has a significant impact on the treatment effects that can be observed. This varies from one disease to the next and as such contributes to lack of consistency in observable utility effects and incremental utility scores. This observation appears to have been omitted from the method development considerations such as reference methods. As a result, we recommend that patients' perspectives obtained via qualitative methods are taken into consideration in the ongoing methods development in health state descriptions for generic utility instruments. Also, as a more immediate contribution to improving decision making, we propose that a content map of the chosen utility measure with patient-reported domains be provided as standard reporting in utility measurement in order to improve the transparency of the trade-offs in relation to patient relevance and consistency.</p

Treatment satisfaction and dissatisfaction in patients with chronic low back pain

This thesis explores treatment satisfaction and dissatisfaction in patients with chronic low back pain (CLBP). Chapters 1 and 2 provide background on CLBP, and treatment satisfaction and dissatisfaction. Chapter 3 presents study 1, the systematic review which identified research concerning treatment satisfaction and dissatisfaction in patients with CLBP. Findings indicated a need to define the concept, and establish appropriate measurement based on patient input and evidence to support the reliability and validity of items. Chapter 4 presents study 2, a qualitative study. Ten patients with CLBP taking medication and/or receiving physiotherapy were interviewed. A conceptual model of CLBP and a thematic map of treatment satisfaction and dissatisfaction were developed. Satisfaction was related to being 'happy' or 'pleased', and maintaining normal functioning. Treatment not working, causing discomfort, or negatively affecting health-related quality of life, as well as inconvenience of medication, lack of information, not feeling involved in treatment decisions, lack of trust and confidence in healthcare professionals, and being misdiagnosed or undiagnosed, were associated with dissatisfaction. Chapter 5 documents the development of the CLBP Treatment Satisfaction Questionnaire, based on patient input from study 2. Cognitive debriefing showed items were relevant and understood by patients. Chapter 6, study 3, explored the psychometric properties of the questionnaire. The longitudinal design involved data collection from 249 patients, some of whom participated in follow-ups. Results indicated that treatment satisfaction/dissatisfaction involves an appraisal of the following seven domains: 'Information Provided about Back Pain and Treatment', 'Burden of Back Pain', 'Impact of Back Pain and Treatment on Relationships', 'Satisfaction with the Treatment Process', 'Problems with Side Effects of Medication', 'Adherence to Physiotherapy', and 'Medication Acceptability'. Some evidence of reliability and validity are presented. This thesis concludes with Chapter 7, a discussion of the main findings of the studies, strengths and limitations, and recommendations for future research.EThOS - Electronic Theses Online ServiceMapi ValuesGBUnited Kingdo